GCSE Lab Experiment (Friction)

Objectives: (3 points) 
What is the physics concepts/theory/law to be investigated in this experiment?   It is one or two sentences in your own words.
Experimental Data (3 points): Insert experimental graphs and obtain from the graphs  all the experimental data that will be used for further calculations in Data Analysis.
PART 1.  Static Friction
1a) Cart on the horizontal track
1b) Cart on an inclined plane

Trial	Critical angle (Θ)

 
PART 2.  Kinetic friction
2a)  Cart on the horizontal track
 

Run	acceleration, a

 
2b) Cart on an Incline plane.

Run	acceleration, a

 
Data Analysis (10 points):
 
PART 1. Static Friction
1a) Cart on the horizontal track.

• The experimental value of the coefficient of the static friction µ_s calculated as follows:

(Show equation and calculation)

• The discrepancy between the experimentally determined µ_s and its actual given value has been calculated to be:

(Show equation and calculation)
1b) Cart on an Incline plane

• The experimental value of the coefficient of static friction µ_s is calculated with equation (4) as follows:

(Show equation and calculation

• Determine the discrepancy between the above-calculated value and the given one to compare them: 100%* (| value– expect. value| / expect. value).

(Show equation and calculation)
PART 2.  Kinetic friction
2a)  Cart on the horizontal track

• For run 1 the coefficient of kinetic friction μk is calculated as follows:

(Show equation and calculation

• For run 2 the coefficient of kinetic friction μk is calculated as follows:

(Show equation and calculation)
 

• The average values of coefficient of kinetic friction μk from both runs is:

(Show equation and calculation)

• The discrepancy between the experimental and theoretical values is:

(Show equation and calculation)
2b) Cart on an Incline plane.

• For run 1 the coefficient of kinetic friction μk is calculated as follows:

(Show equation and calculation)

• For run 2 the coefficient of kinetic friction μk is calculated as follows:

(Show equation and calculation)

• The average values of coefficient of kinetic friction μk from both runs is:

(Show equation and calculation)

• The discrepancy between the experimental and theoretical values is:

(Show equation and calculation)
Results (3 points)
State all values in the table with the correct number of significant figures and appropriate units!
Discussion and Conclusion (10 points):
This is the most important part of the lab report. It is where you describe whether your results support the physics principal being investigated in the lab. Begin the discussion with the purpose of the experiment. Briefly explain the theory concept that was tested. Then state only the key results (with uncertainty and units) quantitatively with numerical values; do not provide intermediate quantities. Discuss the relationship between your row measurements and your final results; the relationship between quantities in the graph; relationship between the independent and dependent variables. All questions below were also answered in the narrative form.